Working like a dog.

Dogs' impeccable sense of smell is well known, making canines ideal for locating bombs and drugs. However, they are also able to smell cancer, low blood sugar, and even depression. In addition, dogs are sometimes employed to alert their owners to upcoming epileptic seizures, though researchers are uncertain if seizure dogs are responding to smells or subtle behavioral changes. Regardless of how they are able to do it, dogs prove that they really are man's best friend.